lentogenic
/ˌlɛntə(ʊ)ˈdʒɛnɪk/Veterinary Med. and Virology
adjective
Designating strains of Newcastle disease virus that replicate slowly and are not very virulent; of, relating to, or consisting of such a strain.
Origin
1950s. From classical Latin lentē̄ slowly + -o- + -genic.